In the preparation of semiconductor devices such as IC and LSI, it has heretofore been a common practice that various steps such as photolithographic step using a photoresist composition, etching step, impurity diffusion step and wiring step are repeated several times. In the foregoing photolithographic step, a photoresist composition is applied to a semiconductor substrate to form a thin film thereon. The thin film is irradiated with actinic rays through a mask pattern, and then developed to form a resist pattern. As the actinic rays there have been used g-line (436 nm), i-line (365 nm), etc. However, with the enhancement of integration of semiconductor devices, light rays having a shorter wavelength such as far ultraviolet rays and exima laser have been used more and more. The shorter the wavelength of the actinic light rays used is, the more is light reflected from the substrate. This causes a great problem that the resist pattern is liable to local strain (notching) or deterioration of dimensional accuracy due to reflected light. Thus, the interposition of an antireflective coating film between the substrate and the resist layer for the purpose of inhibiting the reflection of light has been noted (see JP-B-3-67261 (The term "JP-B" as used herein means an "examined Japanese patent publication")).
While the wavelength of actinic rays used for this purpose has been reduced more and more, the resolution of resists used for this purpose has been raised higher and higher. However, if a resist composition having a high resolution is applied to a substrate having an antireflective coating film provided thereon, a so-called intermixed layer is liable to be formed at the interface of the resist composition with the antireflective coating film. This causes the generation of bites or thickening at the lower portion of the resist pattern. As a result, the section shape of the resist pattern is deteriorated, making it difficult to produce good semiconductor devices. In order to overcome these difficulties, a method which comprises heat- treating an antireflective coating film at a temperature of higher than 180.degree. C. was proposed. However, this method is disadvantageous in that the dye in the antireflective coating film can be easily sublimated at this high temperature, causing stain on the interior of the apparatus or other troubles. Thus, this approach is not practical.
Under these circumstances, the inventors made extensive studies. As a result, it was found that when an antireflective coating film-forming composition layer is formed by a composition comprising a compound which undergoes crosslinking reaction when irradiated with actinic rays and a dye, and then entirely irradiated with actinic rays to form an antireflective coating film, the production of an intermixed layer can be inhibited without the necessity of high temperature treatment, thereby making it possible to form a resist pattern having an excellent dimensional accuracy and section shape free of bite or thickening at the lower interface thereof.